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Related papers: Optimal Cloning and Singlet Monogamy

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The overlap of a large quantum state with its image, under tiny translations, oscillates swiftly. We here show that complete orthogonality occurs generically at isolated points. Decoherence, in the Markovian approximation, lifts the…

Quantum Physics · Physics 2010-03-10 Eduardo Zambrano , Alfredo M Ozorio de Almeida

No-cloning theorem forbids perfect cloning of an unknown quantum state. A universal quantum cloning machine (UQCM), capable of producing two copies of any input qubit with the optimal fidelity, is of fundamental interest and has…

We consider systems of interacting spins and study the entanglement that can be localized, on average, between two separated spins by performing local measurements on the remaining spins. This concept of Localizable Entanglement (LE) leads…

Quantum Physics · Physics 2007-05-23 M. Popp , F. Verstraete , M. A. Martin-Delgado , J. I. Cirac

We show that any measure of entanglement that on pure bipartite states is given by a strictly concave function of the reduced density matrix is monogamous on pure tripartite states. This includes the important class of bipartite measures of…

Quantum Physics · Physics 2019-04-10 Yu Guo , Gilad Gour

We study the entanglement properties of the output state of a universal cloning machine. We analyse in particular bipartite and tripartite entanglement of the clones, and discuss the ``classical limit'' of infinitely many output copies.

Quantum Physics · Physics 2022-10-12 D. Bruss , C. Macchiavello

Nuclear entanglement is a flagship in the interdisciplinary direction of nuclear physics and quantum information science. Spin entanglement, a special kind of nuclear entanglement, is ubiquitous in nuclear structures and dynamics. Based on…

Nuclear Theory · Physics 2024-03-08 Dong Bai

The entangled multipartite systems, specially in pure states, exhibit the phenomenon entanglement monogamy. Such systems also display the phenomenon of Bell nonlocality. Like entanglement monogamy relations, there are Bell monogamy…

Quantum Physics · Physics 2026-01-07 Abhisek Panda , Chandan Datta , Pankaj Agrawal

State-dependent cloning machines that have so far been considered either deterministically copy a set of states approximately, or probablistically copy them exactly. In considering the case of two equiprobable pure states, we derive the…

Quantum Physics · Physics 2009-10-31 Anthony Chefles , Stephen M. Barnett

There exist diverse no-go theorems, ranging from no-cloning to monogamies of quantum correlations and Bell inequality violations, which restrict the processing of information in the quantum world. In a multipartite scenario, monogamy of…

Quantum Physics · Physics 2015-05-26 Debasis Sadhukhan , Sudipto Singha Roy , Debraj Rakshit , Aditi Sen De , Ujjwal Sen

We investigate the concentration of multi-party entanglement by focusing on simple family of three-partite pure states, superpositions of Greenberger-Horne-Zeilinger states and singlets. Despite the simplicity of the states, we show that…

Quantum Physics · Physics 2007-05-23 Berry Groisman , Noah Linden , Sandu Popescu

We consider a quantum many-body system made of $N$ interacting $S{=}1/2$ spins on a lattice, and develop a formalism which allows to extract, out of conventional magnetic observables, the quantum probabilities for any selected spin pair to…

Statistical Mechanics · Physics 2007-05-23 Andrea Fubini , Tommaso Roscilde , Valerio Tognetti , Matteo Tusa , Paola Verrucchi

We investigate the role of symmetric quantum cloning machines (QCMs) in quantifying the mutual incompatibility of quantum observables. Specifically, we identify a cloning-based incompatibility measure whereby the incompatibility of a set of…

Quantum Physics · Physics 2021-09-20 Arindam Mitra , Prabha Mandayam

Of course not, but if one believes that information cannot be destroyed in a theory of quantum gravity, then we run into apparent contradictions with quantum theory when we consider evaporating black holes. Namely that the no-cloning…

High Energy Physics - Theory · Physics 2019-04-09 Andrzej Grudka , Michael J. W. Hall , Michal Horodecki , Ryszard Horodecki , Jonathan Oppenheim , John A. Smolin

It is known that probabilistically mixing an arbitrary pair of pure quantum states, one of which is entangled and the other product, in any bipartite quantum system, one always obtains an entangled state, provided the entangled state of the…

Quantum Physics · Physics 2023-04-25 Saronath Halder , Ujjwal Sen

We provide a fine-grained definition for monogamous measure of entanglement that does not invoke any particular monogamy relation. Our definition is given in terms an equality, as oppose to inequality, that we call the "disentangling…

Quantum Physics · Physics 2018-08-14 Gilad Gour , Yu Guo

In this paper, we study the bipartite entanglement of spin coherent states in the case of pure and mixed states. By a proper choice of the subsystem spins, the entanglement for large class of quantum systems is investigated. We generalize…

Quantum Physics · Physics 2015-06-12 K. Berrada , A. Mohammadzade , S. Abdel-Khalek , H. Eleuch , S. Salimi

Our main result is a monogamy inequality satisfied by the entanglement of a focus qubit (one-tangle) in a four-qubit pure state and entanglement of subsystems. Analytical relations between three-tangles of three-qubit marginal states,…

Quantum Physics · Physics 2018-06-13 S. Shelly Sharma , N. K. Sharma

Genuine high-dimensional entanglement, i.e. the property of having a high Schmidt number, constitutes a resource in quantum communication, overcoming limitations of low-dimensional systems. States with a positive partial transpose (PPT), on…

Quantum Physics · Physics 2018-11-21 Marcus Huber , Ludovico Lami , Cécilia Lancien , Alexander Müller-Hermes

One of the fundamental differences between classical and quantum mechanics is in the ways correlations can be distributed among the many parties that compose a system. While classical correlations can be shared among many subsystems, in…

Quantum Physics · Physics 2020-09-09 Marcos L. W. Basso , Jonas Maziero

We consider a network of n spin 1/2 systems which are pairwise interacting via Ising interaction and are controlled by the same electro-magnetic control field. Such a system presents symmetries since the Hamiltonian is unchanged if we…

Quantum Physics · Physics 2018-05-23 Francesca Albertini , Domenico D'Alessandro